The 88 nations of the International Whaling Commission held two days of intense closed-door talks on a proposal to ease the 25-year-old ban on commercial whaling in exchange for smaller kills by the three countries that claim exemptions to the moratorium on hunting for profit.

About 1,500 animals are killed each year by Japan, Norway and Iceland. Japan, which kills the majority of whales, insists its hunt is for scientific research — but more whale meat and whale products end up in Japanese restaurants than in laboratories.

A key sticking point appeared to be that the agency declared a whaling sanctuary in 1994 in the Southern Ocean south of Australia but Japanese ships hunt freely there because the agency has no enforcement powers. Australia has already launched a complaint against Japanese whaling at the International Court of Justice in The Hague, the U.N.'s highest court.

Acting IWC chairman Anthony Liverpool told an open meeting Wednesday that "fundamental positions remained very much apart."

"After nearly three years of discussions, it appears our discussions are at an impasse," said chief U.S. delegate Monica Medina.

Japanese whaling commissioner Yasue Funayama said her country had offered major concessions to reach a compromise and blamed anti-whaling countries that refused to accept the killing of a single animal.

"We must rise above politics and engage in a broader perspective," Funayama said.

Anti-whaling countries sought to end Japan's hunting forays into a southern ocean whaling sanctuary, ban the international trade in whale meat and to set firm quotas for the whaling nations for the next 10 years.

The proposed deal would let Japan kill 400 whales in the southern sanctuary for the next five years, which many countries thought was too high and which Japan saw as a major concession. Japan set a 2009 quota for itself to kill over 900 whales, but did not reach that figure due to harassment from anti-whaling groups

Australia and a bloc of Latin American countries held firm on zero whaling in the Antarctic ocean, said a delegate from a non-whaling country. He spoke on condition of anonymity because he was not authorized to speak to the media.

Iceland also refused to consider any deal restricting the international sale of whale products, he added.

Environmentalists blamed Japan for the breakdown.

"If Japan had agreed to a phase out in the southern ocean, there would have been a good chance" for a deal, said Wendy Elliott of WWF.

Other conservationists expressed relief that the 25-year ban on whaling was not lifted.

"Had it been done here, this deal would have lived in infamy," said Patrick Ramage, of the International Fund for Animal Welfare.

It was unclear if private discussions will continue until the meeting's scheduled close on Friday. Many delegations called for a one-year break in efforts.

Formal talks will center on issues like preventing collisions by whales and ships, the effects of climate change and a discussion on a planned Russian oil exploration in the seasonal feeding grounds of the endangered gray whale.

Some environmentalists have accused Japan of vote-buying, using development aid money and personal favors to swing small, poorer nations to its side in the whaling debate.

But the delegate from St. Kitts and Nevis, Daven Joseph, told the media and environment groups to stop such allegations. "We have been accused of being surrogates. That is not the case," he said.

Liverpool, a diplomat from Antigua and Barbuda and its ambassador to Japan, has been quoted by a British paper as admitting that Japanese interests have paid hotel bills for him and says he sees nothing "odd about that."

The whaling commission was created after World War II to conserve and manage whale stocks. Tens of thousands of animals were killed each year until 1986, when the IWC adopted the moratorium.